Anonymous discussion forum

ABSTRACT

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for enabling anonymous posting of content, e.g., over a network (e.g., the internet). In some instances, users may inform a system of various attributes of the user, for example, job title, skills, and/or interests. The system may group similar users together. In some cases, users grouped together can see messages posted by the other users in the group in an anonymous discussion forum. In other cases, users grouped together can have other users in the group presented to them as potential options of users to follow, e.g., as part of an anonymous social media platform. In some implementations, users can identify particular user subsets to view posted content.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of co-pending U.S.provisional patent application Ser. No. 62/143,724, titled “AnonymousDiscussion Forum,” filed on Apr. 6, 2015, the disclosure of which isherein incorporated by reference in its entirety.

TECHNICAL FIELD

This specification relates to anonymous content posting and, inparticular, to the anonymous exchange of content in online forums suchas, e.g., discussion forums and social media platforms.

BACKGROUND

An online discussion website such as a message board, or a social mediawebsite, provides an online forum where users of the website can holddiscussions by posting messages. In message boards, messages posted fora particular topic can be grouped into a thread, often referred to as aconversation thread. A user interface (e.g., a web page) for an onlineforum can contain a list of threads or topics. Each thread can beexpanded to a list of messages, often arranged in a chronological order.Each message typically comprises a text message, a time stamp, and anauthor identified by a real name or a user name (e.g., for an account ofthe online forum). In social media websites, users are typicallyfollowed by other users and/or select other users to follow. In thiscontext, “follow” means being able to see content posted by the followeduser. Users typically select other users to follow based on the identityof the other users, which is provided by the social media platform,e.g., by providing a real name, a user name, and/or a picture.

SUMMARY

In general, one aspect of the subject matter described in thisspecification can be embodied in methods that include the actions ofidentifying a first group of users of a plurality of users, where eachof the users in the first group has a respective likeness score inrelation to a first user that satisfies a threshold, and where each userof the first group is permitted to send anonymous messages through arespective account to the first user; identifying a plurality of firstanonymous messages received in an account of the first user, each firstmessage having been authored by a respective user of the first group;and obtaining user input of the first user indicating a negativeresponse to a particular first message and, based thereon, removing anauthor of the particular first message from the first group such thatthe author is no longer permitted to send messages to the first userthrough the account of the author. Other embodiments of this aspectinclude corresponding systems, apparatus, and computer programs.

These and other aspects can optionally include one or more of thefollowing features. The aspect can further comprise, after removal ofthe author from the first group, determining respective likeness scoresof one or more particular users in relation to the first user and, basedthereon, adding the particular users to the first group or removing theparticular users from the first group. Removing the particular usersfrom the first group can further comprise determining that respectivelikeness scores of the particular users no longer satisfy the thresholdand, based thereon, removing the particular users from the first groupsuch that the removed particular users are no longer permitted to sendmessages to the first user through their respective accounts. Adding theparticular users to the first group can further comprise determiningthat a second group of one or more of the plurality of users haverespective likeness scores that satisfy the threshold after removal ofthe author from the first group, and adding the second group of users tothe first group of users such that each user of the second group ispermitted to send anonymous messages through a respective account to thefirst user. Determining the respective likeness scores of the particularusers in relation to the first user can comprises identifying one ormore discriminating attributes, obtaining a weighted vector ofattributes for the first user and for each of the particular users,adjusting a respective weight of the discriminating attributes in eachof the vectors, and calculating the respective likeness score of each ofthe particular users as a difference between the weighted vector ofattributes of the particular user and the weighted vector of attributesof the first user. Identifying one or more discriminating attributes cancomprise identifying one or more discriminating attributes of theauthor. Identifying the discriminating attribute can comprise clusteringthe plurality of users based on respective attributes of the users toidentify the discriminating attributes that influence clustermembership. Clustering can comprise, for different pairs of users of theplurality of users, calculating a respective distance between the usersof the pair based on the respective attributes of the users in the pair,and clustering users based on the distances. A particular attribute cancomprise one or more respective anonymous answers, submitted throughrespective accounts of the particular users to one or more questionssubmitted through the account of the first user. A particular attributecan comprise a profession, a company, time of employment, location ofemployment, or an attribute that is unrelated to employment. Aparticular attribute can comprise a respective positive response to ananonymous message through an account of a user.

In general, another aspect of the subject matter described in thisspecification can be embodied in methods that include the actions ofreceiving profile information from a plurality of users, the profileinformation comprising at least one attribute of each user; providing toa first user options of other users for the first user to follow withoutrevealing the identity of the other users; receiving a message postingfrom the first user; and providing the first user with an option toselect a subset of the plurality of users that can view the messageposting. In some cases, the other users have at least one attribute incommon with the first user. In other cases, the other users all share acommon attribute (e.g., a job title). Other embodiments of this aspectinclude corresponding systems, apparatus, and computer programs.

These and other aspects can optionally include one or more of thefollowing features. The at least one received attribute may include ajob title and/or a personal characteristic. The personal characteristicmay relate to how a user performs their job (e.g., a parental status, apolitical status, a religious status, an immigrant status, etc.). Insome cases, the identified subset can include users that follow thefirst user. In some cases, the identified subset can include users thathave at least one attribute in common with the first user. In certaininstances, the received attribute can include a first attribute and asecond attribute, and the identified subset can include users that haveboth the first attribute and the second attribute in common with thefirst user. In some cases, the identified subset can include users thathave a particular attribute (e.g., a job title) that is different thatthe first user. In some instances, the received attribute can include aplace of employment, and the identified subset can include colleagues ofthe first user. The method can further include the action of displayingthe message posting to the subset of the plurality of users identifiedby the first user, without revealing the identity of the first user. Thedisplaying step may include presenting a first avatar associated withthe first user. The method can further include the actions of receivingat least one comment posting from the first user on the message posting;displaying the at least one comment posting along with the first avatar;receiving a second message posting from the first user; and displayingthe second message along with a second avatar, such that a user viewingthe message posting and the at least one comment posting can determinefrom the first avatar that they are both posted by the same user, whilea user viewing the message posting and the second message posting cannotdetermine that they are both posted by the same user. In some instances,the displaying step further includes the action of indicating to a userviewing the message posting that the message posting was received from auser that has a particular attribute (e.g., a job title) that isdifferent than the viewing user.

In general, another aspect of the subject matter described in thisspecification can be embodied in methods that include the actions of:receiving at least one message posting from a posting user; assigning atopic tag to the message postings; and determining a topic reputationalscore for the posting user based on an amount of feedback received onthe message postings and the topic reputational scores of the otherusers providing feedback. In some instances, the method can furtherinclude identifying other users interested in the topic; and presentingthe message postings to the other users at a location based on the topicreputational score of the posting user. Other embodiments of this aspectinclude corresponding systems, apparatus, and computer programs.

Particular implementations of the subject matter described in thisspecification can be implemented to realize one or more of the followingadvantages. The system described herein enables content to be exchangedanonymously, e.g., a part of an anonymous discussion forum and/or ananonymous social media platform. The system may automatically form agroup of like users based on similarity in respective attributes ofusers of the system. Users of the system can define their own attributesin forms of questions and corresponding answers. Each user in a group oflike users can send anonymous messages through a respective account toother users in the group. Membership in a group of like users can beautomatically updated over time by the system. Membership in the groupof like users can be automatically updated based on one user's negativeresponse to another user's anonymous message, for example. The anonymoussocial media platform can provide users with options of other users tofollow without revealing the identity of the other users. The platformcan allow a particular user to select a subset of other users that canview a message posted by the particular user.

The details of one or more implementations of the subject matterdescribed in this specification are set forth in the accompanyingdrawings and the description below. Other features, aspects, andadvantages of the subject matter will become apparent from thedescription, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example system for anonymous content posting.

FIG. 2 illustrates an example user interface for a conversation threadin an anonymous discussion forum.

FIG. 3 illustrates an example user interface for enrolling a user in ananonymous content posting system.

FIGS. 4A and 4B illustrate example user profile forms.

FIG. 5 is a flowchart of an example method for determining a group oflike users in relation to a given user.

FIG. 6 illustrates an example user interface for an anonymous socialmedia platform.

FIG. 7 illustrates an example user interface showing comment postings ona message posting.

FIG. 8 illustrates an example user interface for generating content.

FIG. 9 illustrates an aspect of an example user interface for selectingthe viewers of a particular content posting.

FIG. 10 illustrates another aspect of an example user interface forselecting viewers of a particular content posting.

FIG. 11 illustrates an example user interface for searching for usersubset groups to select as viewers of a particular content posting.

FIG. 12 illustrates another aspect of an example user interface forselecting viewers of a particular content posting.

FIG. 13 illustrates an example client device that can be used in certainimplementations of the disclosure.

Like reference numbers and designations in the various drawingsgenerally indicate like elements.

DETAILED DESCRIPTION

FIG. 1 illustrates an example system for anonymous content postingimplemented by a server system 122. The server system 122 providesfunctionality for posting anonymous messages and grouping like users.The server system 122 comprises software components and databases thatcan be deployed at one or more data centers 121 in one or moregeographic locations, for example. The server system 122 softwarecomponents may include a message server 112, group manager 114, machinelearning system 116, onboard manager 117, and/or profile manager 118.The software components can comprise subcomponents that can execute onthe same or on different individual data processing apparatus. Theserver system 122 databases may include a user data database 132, groupdata database 134, attributes database 136, and messages database 138.The databases can reside in one or more physical storage systems.Example features of the software components and data processingapparatus will be further described below.

The message server 112 is a software component that may send and receiveanonymous messages to and from users' client devices through one or moredata communication networks 113 such as the Internet, for example. Auser of the system 122 can access a user interface (e.g., user interface124 a) of a client application (e.g., client application 123 a) such asa web browser or a special-purpose software application executing on theuser's client device (e.g., client device 120 a) to access the anonymouscontent posting forum implemented by the server system 122. Althoughthis application will describe many functions as being performed bysystem 122, in various implementations, some or all functions performedby system 122 may be performed locally by a client application (e.g.,client application 123 a). The client application can communicate withthe message server 112 using Hypertext Transfer Protocol (HTTP), anotherstandard protocol, or a proprietary protocol, for example. A clientdevice (e.g., 120 a, 120 b, 120 c) can be a mobile phone, a smart watch,a tablet computer, a personal computer, a game console, or an in-carmedia system. Other types of client devices are possible. The system 122of FIG. 1 can enable several anonymous content posting functions,described in more detail below.

In various implementations, the system 122 can enable an anonymousdiscussion forum. A user can submit messages to the system 122 for otherusers in a group of users that are similar to the user to view andrespond to. Each user of the system 122 can have an individual accountwith the system 122 through which they can submit and receive messages.In some cases, submitted messages are automatically shared with users inthe user's group.

A given pair of users can be similar to each other if their respectivecharacteristics or attributes are, in the aggregate, determined to besimilar to a satisfactory degree. Membership in a group of similar userscan change over time and can be determined automatically by the system122. The details of identifying attributes of users, determininglikeness between users based on attributes, and determining a group oflike users will be further described below.

By way of illustration, a user of a client device (e.g., client device120 a) can submit a new message to the user interface (e.g., userinterface 124 a) of a client application (e.g., client application 123a) executing on the client device. The client application can transmitthe new message to the message server 112 which can store the message inmessage database 138 along with a time stamp indicating when the messagewas submitted by the user, an identifier of the user (or user account)that submitted the message, and an identifier of a conversation threadthat the message belongs to (if any). A message can comprise text, imagecontent, video content, audio content, multimedia content, or acombination of these. The identifier of the user can be an internalidentifier of the user's account on the server system 122, for example.The identifier of the conversation thread may include a topic such asthe subject of the conversation and, optionally, an indication ofwhether the message is the first message of the conversation thread oris a follow-up message. In various implementations, the message server122 removes from the new message any real-world identificationinformation (e.g., name, phone number, email address, mailing address)that the user may have entered, before storing the new message in themessages database 138. In one implementation, the message server 122discards new messages including real-world identification informationand does not store them in the messages database 138. The message server122 then makes the new message available for viewing by users in theuser's group.

A user of the system 122 can, through a user interface (e.g., userinterface 124 b) of a client application (e.g., client application 123b) running on the user's client device (e.g., client device 124 b),retrieve messages for one or more conversation threads started by theuser or by users in the user's group. The client application can send arequest to the system 122 to retrieve the messages. In response to therequest, the message server 112 can obtain the requested messages fromthe messages database 138 and, before sending them to the requestingclient device, strip the messages of all identifying information, suchas the identifiers of the users that authored the messages, so that theuser will not know, for any given message, who the author of the messageis. Upon receiving the anonymous messages, the client applicationdisplays in its user interface the anonymous messages (in one or moreconversation threads), as shown for example in FIG. 2.

FIG. 2 illustrates an example user interface 200 for presenting aconversation thread. The user interface 200 displays a conversationthread including anonymous messages 211, 212, 213, 214, and 215. Eachanonymous message includes message content (e.g., 221, 222, 223) such astext or image content. The user interface 200 can also include a subjector topic (e.g., 250) of the conversation thread. Note that identifyinginformation such as user identifiers are absent in the messages of theconversation thread. By removing identifying information from messagesprovided to users, the message server 112 enables anonymous messageexchanges between users of the system 122 through their respective useraccounts. For instance, user A can submit a message as part of aconversation thread started by user B. User B can view the particularmessage authored by user A without knowing the identity of user A, sinceno identifying information is provided by the message server 112 to userB. In this way, user A effectively sent an anonymous message to user Bthrough user A's account on the system 122.

In some implementations, and as illustrated in FIG. 2, each anonymousmessage in the user interface 200 can also include a selectable icon(e.g., 251) for the viewing user to provide a positive response to themessage (e.g., “Thank you”), and a selectable icon (e.g., 252) for theuser to provide a negative response to the message (e.g., “No thanks”)In response to the user's selection of a positive or negative responseto a particular anonymous message (e.g., 214), the client applicationdisplaying the user interface 200 transmits the response, an identifierof the particular anonymous message, and an identifier of the user, tothe message server 112. The message server 112 can, based on theidentifier of the particular anonymous message, access the messagesdatabase 138 to determine the author of the particular anonymousmessage. The message server 112 can store in the attributes database 136the response, in reference to the user and the author. That is, themessage server 112 can store in the attributes database 136 an attributeof the user's positive or negative response (described below) to theauthor of the particular anonymous message. In some implementations, themessage server 112 provides, for a particular response, an anonymousacknowledgement message to the author of the particular anonymousmessage. The anonymous acknowledgement message may be created withoutthe identifying information of the user providing the response (e.g.,“Someone has thanked you for your comment.”). For instance, the messageserver 112 can send a text message with the anonymous acknowledgementmessage to the author of the particular anonymous message. As anotherexample, the message server 112 can post the anonymous acknowledgementmessage in a user interface for the anonymous discussion forum that theauthor of the particular anonymous message can access from his/herclient device.

In various implementations, the user interface 200 for presenting aconversation thread can include an indication of a number of messages inthe conversation thread. The user interface can also include anindication of a number of positive and/or negative responses (e.g., onmessages of the conversation thread) that a viewer of the conversationthread had submitted to the system 122.

In some implementations, the group manager 114 can update membership ofa group of like users in relation to a user in response to changes ofone or more attributes associated with the user or one or more likeusers in the group. For example, when the system 122 receives from theuser an indication of a negative response to a particular user'sanonymous message in a conversation thread, the group manager 112 mayremove the particular user from any group of like users in relation tothe user, e.g., permanently or for an extended period of time (e.g.,three months). In this example, the user effectively “banishes” theparticular user from his/her group of like users, and the user will notsee anonymous messages authored by the particular user again (or atleast for an extended period of time); that is, the particular user isno longer permitted to send anonymous messages to the user through theparticular user's account on the anonymous discussion forum implementedby the system 122. In various implementations, after the particular useris banished by the user, a third user in the user's group can see astrike-out or gray-out copy of the particular user's message in theconversation thread, indicating the message has been banished from theconversation thread. In this way, the third user can ignore the banishedmessage while commenting on the conversation thread.

A user can enroll with the system 122 by submitting a phone number tothe system, for example. Other types of enrollment information arepossible including email addresses. In reference to FIG. 1, the onboardmanager 117 is a software component that may manage enrollment of users.The onboard manager 117 can provide a web page to a user's client devicethat requests information from the user, for example, as illustrated bya graphical user interface 300 in FIG. 3. The graphical user interface300 is an example user interface for enrolling the user to the system122. The user can access the graphical user interface 300 in a browserwindow of a web browser running on the user's client device. A userinterface for enrolling the user to the anonymous discussion forum canalso be presented to the user by a client application (e.g., clientapplication 123 a) of the user, for example. In addition to requesting aphone number, the graphical user interface 300 may request the user toanswer a plurality of questions that ask for one or more attributes ofthe user. For example, the questions can ask the user for his/herprofession (331), company (332), time of employment (333), and locationof employment (334). The attribute questions can inquire aboutattributes that are unrelated to employment such as, for example, afavorite hobby, favorite food, and a location the user often goes tobesides home and work. The graphical user interface 300 (or a userinterface presented by a client application) can also let the userselect a particular category (e.g., work, leisure, sports, food) and askthe user attribute questions corresponding to the selected category(e.g., “What sports do you play every week?”, “What is your favoritesports team?”, “Who was your favorite athlete when you growing up?”).Other attribute questions are possible.

The user can join the system 122 by, for example, providing a phonenumber and answers to the attribute questions (e.g., “A start-upcompany”, “I'm the CTO”, “2 years”, “San Francisco”). An answer to anattribute question can be unstructured text. Upon receiving anindication from the user (e.g., by selecting a submit icon 350), the webbrowser displaying the onboarding user interface 300 can transmit thephone number and answers (e.g., attributes) to the onboard manager 117.The onboard manager 117 may create a user account record for the userbased on the phone number and store the user account record in the userdata database 132. In some implementations, a user's phone number (e.g.,his/her real-world identification information) is stored in a separatedatabase that provides mapping between the user's phone number and aninternal identifier of the user. In such cases, only the internalidentifier of the user may be stored in the user data database 132,group data database 134, attributes database 136, and messages database138, for referencing the user's data in these databases. In addition,the onboard manager 117 may store the attributes (e.g., the user'sanswers to the attribute questions) in the attributes database 136. Thesystem 122 can determine whether two users are similar based on theseattributes (described further below). In some instances, the user'sphone number (e.g., the user's identity) and attributes are not providedto another user by the system 122.

In reference to FIG. 1, the profile manager 118 is a software componentthat may manage profiles for users of the system 122. A profile can be acollection of one or more attributes of a user. In some instances,instead of asking every system user for information of pre-determinedattributes (e.g., home city, work city, age, schools attended, and soon), the profile manager 118 provides to a user a user profile form(e.g., a web page) that allows the user to create a question and providean answer to his/her own question. That is, in such instances, eachattribute is a pair of a question and a corresponding answer. Thisallows a user to define his/her own attributes, in addition to theattributes described in reference to FIG. 3. A question and itscorresponding answer in a question-answer attribute can be unstructuredtext. FIG. 4A is an example user profile form 401. For example, the usercan create a question “What is your favorite vacation spot?” (411) andprovide an answer “Yosemite National Park” (412). The user can createquestions and provide corresponding answers in a user profile formdisplayed in a browser window of a web browser running on the user'sclient device. After receiving from the user an indication of completingthe user profile form (e.g., after detecting the “Enter” keystroke inthe answer field 412), the browser can transmit the question-answerpairs (question-answer attributes) to the profile manager 118. Theprofile manager 118 can then store the question-answer pairs in theattributes database 136 in reference to the user.

In some instances, the profile manager 118 can post a question submittedby a first user to a second user. The second user can be another user inthe first user's group. In various implementations, the second user canbe a user currently not in the first user's group, but may be added tothe first user's group based on the second user's answer to the firstuser's question. The profile manager 118 can post the question submittedby the first user to the second user, for example, in another userprofile form 421 illustrated in FIG. 4B. The profile manager 118 cancreate the user profile form 421 including a question proposed by thefirst user 431 (e.g., “What's your favorite vacation spot?”), andtransmit the user profile form 421 to the second user's client device.The second user can enter an answer 432 (e.g., “Napa Valley”) in theuser profile form 421 displayed by a web browser running on the seconduser's client device. The browser can transmit the question-answer pair(question-answer attribute) to the profile manager 118. The profilemanager 118 can then store the question-answer pair in the attributesdatabase 136 in reference to the second user. The system 122 candetermine whether (and how) two users are similar based on thequestion-answer attributes and other attributes (described furtherbelow).

In certain implementations, because any user's identity and messagessubmitted through his/her account are anonymous to another user of thesystem 122, a user cannot identify and determine membership of a groupof like users. Instead of allowing every user in the system 122 to haveaccess to every other user's submitted messages, in some cases, thesystem 122 automatically and dynamically determines membership of agroup of like users that are similar and can share submitted messages.

In reference to FIG. 1, the group manager 114 is a software componentthat may determine membership of a group of users of the system 122.Each user in a given group may be permitted to view anonymous messagessubmitted by others in the group and to submit messages through theirrespective account for viewing by the other users. For example, thegroup manager 114 can identify a group of users that are similar to agiven user based on a likeness function. The likeness function cancalculate a likeness score that indicates how alike one user is toanother based on a comparison of the attributes of the two users. Inthis way, the group manager 114 (or another software component of thesystem 122) can select one or more attributes, or use different sets ofattributes, to filter all users of the system 122 into different groupsof like users. For example, the group manager 114 can determine a groupof like users that have similar attributes in employment (e.g.,programmers who have been with a startup in San Francisco for 3 years).The group manager 114 can further filter these programmers into groupsof like users with similar attributes, e.g., programmers who have beenwith a startup in San Francisco for 3 years and love dogs, programmerswho have been with a startup in San Francisco for 3 years and love cats,and programmers who have been with a startup in San Francisco for 3years and do not like pets at all. In various implementations, the groupmanager 114 can determine a first group of like users based on a firstset of attributes (e.g., programmers in San Francisco), and determineone or more particular question-answer attributes that can filter thefirst group of like users into distinct subsets of like users (e.g.,programmers in San Francisco who like Coke, programmers in San Franciscowho like Pepsi, programmers in San Francisco who like smoothies, etc.).The group manager 114 (and/or the profile manager 118) can post one ormore questions for the particular question-answer attributes (e.g.,“What is your favorite drink?”) to other users of the system 122 (e.g.,other programmers in San Francisco, or users that work in San Francisco)to identify groups of like users. That is, the system 122 can constructand post questions to a user (e.g., to determine question-answerattributes) based on other attributes (e.g., job attribute, location,etc.) of the user.

In certain implementations, the likeness score can be a numerical valueor an indication of the degree to which two users are alike (e.g., “veryalike,” “somewhat alike,” “not alike,” etc.). For example, if thelikeness score is a numerical value is between 0 and 1 inclusive, thenthe value 0 indicates that the users are not alike, the value 1indicates that the users are very alike, and a value in between 0 and 1indicates that the users are more alike (closer to 1) or less alike(closer to 0). Of course, the polarity of the likeness score can be theopposite as well (e.g., 0 indicates that the users are very alike and 1indicates that the users are not alike). In any case, in someimplementations, a likeness score threshold can be used to determinegroup membership; that is, a likeness score that satisfies a thresholdvalue determines which users are in a given group. In the example above,the threshold can be a value between 0 and 1. In furtherimplementations, membership in a group can be limited to a number ofusers that are most alike to a given user based on their likenessscores. In this way, the message server 112 can moderate how many users'messages can be seen by the first user (e.g., so as to not overwhelm thefirst user with too many messages, or a very long conversation thread).

In some implementations, the group manager 114 determines a likenessscore of a second user of the system 122 in relation to the first userby representing one or more attributes as a vector in a feature space,where each attribute is an element of the vector and represents arespective feature in the feature space. In some implementations, thelikeness score is the cosine distance between the attribute vectors ofthe two users; that is, the likeness score is a measure of similaritybetween two vectors (e.g., A and B below) of an inner product space thatmeasures the cosine of the angle between them.

${similarity} = {{\cos (\theta)} = {\frac{A \cdot B}{{A}{B}} = \frac{\sum\limits_{i = 1}^{n}{A_{i} \times B_{i}}}{\sqrt{\sum\limits_{i = 1}^{n}{\left( A_{i} \right)^{2} \times \sqrt{\sum\limits_{i = 1}^{n}\left( B_{i} \right)^{2\;}}}}}}}$

In some implementations, the likeness score is calculated as a weightedcosine distance between the attribute vectors (weight selection isdescribed below). For example, for vectors u and v, with weight vectorw, the weighted cosine is:

$\frac{\sum\limits_{i}{w_{i}*u_{i}*v_{i}}}{\sqrt{\left( {\sum\limits_{i}{w_{i}*u_{i}^{2}}} \right)*\left( {\sum\limits_{i}{w_{i}*v_{i}^{2}}} \right)}}$

Other ways of calculating the likeness score are possible. As anotherexample, given two users with two sets of attributes, the likeness scorebetween the two users can be the cardinality of the intersection of theattribute sets divided by the cardinality of the union of the attributesets.

In some instances, attributes such as positive responses to messages andbanishments of users can likewise be represented as elements of anattribute vector. For example, positive message responses (or “positivesignals”) and/or negative message responses (or “negative signals”) canbe represented as vectors for users who authored the messages.

A textual attribute, such as an answer to a question, may be representedas natural language text. For processing efficiency, for example, thesystem 112 can simplify textual attributes into a representationsuitable for inclusion as an element in an attribute vector. In oneimplementation, this can be accomplished by identifying nouns and otherkey words in the text and determining which one(s) bests represent thetext. The identified nouns/keywords can then be mapped to numericalcodes. In another implementation, a bag-of-words model can be used torepresent the text of an attribute as a vector where each entry of thevector represents a count of occurrences of a dictionary word in thetext. In yet another implementation, words in a sentence are tagged tocorresponding parts-of-speech (e.g., noun, verbs, adjectives, adverbs,pronoun, and so on) and the sentence is analyzed by modeling the tagswith a hidden Markov model. For example, words tagged as nouns and anadjective describing the tagged nouns in a question (e.g., “What is yourfavorite vacation destination?”) and words tagged as nouns in an answer(e.g., “Mine is Seattle.”) can be a question-answer attribute (e.g.,favorite vacation destination-Seattle). Other representations of naturallanguage text are possible.

In further implementations, and as described above, the likeness scorecan be calculated as the weighted cosine distance between the attributevectors of two users. In some instances, the weights can be determinedby the machine learning system 116. For instance, the machine learningsystem 116 can identify one or more discriminating attributes, andadjust the vectors in the vector space by adjusting weightscorresponding to the discriminating attributes. Attributes that areconsidered more discriminating than others can be given greater weight.For instance, the machine learning system 116 can use a clusteringanalysis algorithm that clusters users based on respective attributes,and identifies discriminating attributes that influence clustermembership. The clustering analysis algorithm can cluster users bycalculating a distance (e.g., cosine distance) between a pair of usersbased on their respective attributes, and cluster the users based on thedistances. As another example, the clustering analysis algorithm cancluster users based on density of user vectors in the attribute vectorspace. Other example machine learning algorithms for identifyingdiscriminating attributes are possible.

In some implementations, the group manager 114 can determine membershipof a group of like users in the system 122 in relation to a user andstore the group membership in the group data database 134. The groupmanager 114 can update the group membership periodically (e.g., everyhour, every day at a particular time, etc.) and store the updated groupmembership in the group data database 134.

The group manager 114 can also determine membership of a group of likeusers in relation to a user “ad hoc,” for example, in response to auser's request for anonymous messages. For example, a client applicationrunning on the user's client device can send a request to the messageserver 112 to receive anonymous messages in one or more conversationthreads. The message server 112 can notify the group manager 114 aboutthe user's request. The group manager 114 can update (or create) a groupof like users in relation to the first user, and provide the like usersin the group to the message server 112. The message server 112 mayobtain messages associated with the like users from the messagesdatabase 138, strip out any identifying information from the messages,and provide the anonymous messages to the requesting client application.The client application can display to the user the anonymous messages inits user interface. As another example, to find additional like-mindedpeople, a first user can update an attribute (e.g., a job titleattribute, an answer to an attribute question, etc.), or create a newattribute (e.g., a question-answer pair) by submitting new attributeinformation through, for example, user interfaces 300, 401, 421, of aclient application running on the first user's client device. The clientapplication can send the new attribute information to the server system122 to be stored in the attributes database 136. The group manager 114can update a group of like users in relation to the first user based onthe latest attributes stored in the attributes database 136, and storethe group membership in the group data database 134.

FIG. 5 is a flow chart of an example method for determining a group oflike users in relation to a user of an anonymous content posting system.The method can be implemented using software components executing on oneor more data processing apparatus that are part of the data center 121described above. The method may include identifying a first group ofusers of a plurality of users, where each of the users in the firstgroup has a respective likeness score in relation to a first user thatsatisfies a threshold, and where each user of the first group ispermitted to send anonymous messages through a respective account to thefirst user (Step 502). The method may include identifying a plurality offirst anonymous messages received in an account of the first user, eachfirst message having been authored by a respective user of the firstgroup (Step 504). The method may include obtaining user input of thefirst user indicating a negative response to a particular first messageand, based thereon, removing an author of the particular first messagefrom the first group such that the author is no longer permitted to sendmessages to the first user through the account of the author (Step 506).

In various implementations, the techniques described in this applicationcan be used to perform other functions, in addition to or as analternative to, establishing an anonymous discussion forum. For example,the techniques described herein can be used to establish an anonymoussocial media platform. In various instances, a single system 122 and/orclient application can offer one, some, or all of the functionsdescribed herein. For brevity, this disclosure refers to softwarecomponents that perform similar tasks using the same reference numeralregardless of the function being performed by the system 122 (e.g.,establishing an anonymous discussion forum, establishing an anonymoussocial media platform, etc.); however, in various embodiments system 122can include separate software components for separate functions. Asdescribed above, in some instances users can interact with onboardmanager 117 and/or profile manager 118 to provide certain informationabout themselves to system 122. For example, users can inform the system122 of their profession/job title. In some cases, users can inform thesystem 122 of certain skills they have, which may or may not be relatedto their job, e.g., UI designers, iOS programmers, etc. In addition,users can inform the system 122 of other attributes, which in some casescan be personal characteristics that relates to how the user performshis/her job. A few non-limiting examples include, whether the user is aparent, whether the user is an immigrant, the user's political beliefs,and/or the user's religious beliefs. In some cases, users can alsoinform the system 122 of their employer.

As described above, upon receiving user information, the group manager114 can identify other users that are similar to a particular user,e.g., based on the attributes of the particular user. In some instances,system 122 provides to a particular user the other users identified asbeing similar to the particular user, as potential options of users to“follow.” In this disclosure, the term “follow” refers to a conceptwhereby if a particular user “follows” another user, under certaincircumstances (described below), the particular user will be able toview (e.g., on a client device) content posted by the followed user. Invarious embodiments, other terms could be used by the system in place ofthe term “follow” (e.g., “listen”). In other instances, upon receivinguser information, the system 122 may automatically have the particularuser follow (i.e., “listen to”) a group of other users. Thedetermination of which other users will be automatically followed by theparticular user may be based on an attribute (e.g., job title) of theparticular user. For example, if a particular user is a founder, thesystem 122 may have the particular user automatically follow otherfounders (or, in some cases, other job titles: designers, etc.) Theparticular user may then be given the option to un-follow (i.e., stop“listening to”) certain users, or groups of users.

FIG. 6 illustrates an example user interface 600 that can be provided tousers engaging an anonymous social media platform. FIG. 6 and otherfigures presenting user interfaces in this application include examplelabels that refer to various features displayed by the user interface(e.g., discover, feed, history, etc.). While such labels will be used toreference and describe such features in this application, the featuresmay be presented with different labels as well. The interface 600 caninclude a discover tab 602 that, when selected by a user, presents theuser with potential options of other users to follow. In someimplementations, the potential options of users to follow are presentedwithout revealing their identity. For example, the discover tab 602 maypresent the user with certain attributes of potential users to follow(e.g., job title, parental status, etc.), and in some cases a temporaryavatar, but not the identities (e.g., real names, or other informationallowing an identity to be determined) of the potential users. As oneexample, a user whose attributes include being a designer, a parent, andan immigrant, may be presented with the following other users in thediscover tab 602: (i) a designer, a parent, and not an immigrant; (ii) adesigner, an immigrant, and not a parent; and (iii) a designer, aparent, and an immigrant. The user may then select which other users itwants to “follow.” For example, the user may select to follow user (i)and user (iii), but not user (ii).

In various implementations, user interface 600 may also include a feedtab 604. In some instances, when selected by a user, feed tab 604displays content (e.g., message postings) to the user. The messagepostings may be from other users the user follows, or in some cases fromother users the user does not follow. As described in more detail below,which messages are presented in the feed tab 604 can be dependent uponselections made by the message poster upon posting the message. Ingeneral, the feed tab 604 can display content in any manner that allowsusers to view the posted material. For example, as shown in FIG. 6, eachmessage posting 606 a, 606 b can be displayed as an entry on a verticalscroll. In some instances, the message postings 606 a, 606 b arepresented to other viewers without revealing the identity of the messageposter. In some such cases, each message posting includes a header 608including non-identity revealing information related to the source ofthe message, e.g., particular attributes of the message poster. Themessage posting may also include a generic avatar 610 as another way toidentify the source of the message. Beneath the header 608 may be thecontent 612 of the message (e.g., text, image, video, other multimedia,etc.).

In some instances, the message posting may include a feedback icon 614(e.g., a diamond) that can be selected by viewers to indicate approval(or in some cases disapproval) of the posting. In some instances, themessage posting may include a repost icon 616, which when selected by auser results in the message posting being reposted by the selectinguser.

In some instances, the message posting includes a comment icon 618which, when selected by a user, allows the user to post a comment inreply to the message posting. FIG. 7 illustrates an example appearanceof user interface 600 when users have posted comments 702 a, 702 b on aparticular message posting. Each comment posting 702 a, 702 b caninclude its own feedback icon 704, such that viewing users can providefeedback on the comment postings, separate from the message postingitself. In some instances, the comment postings 702 a, 702 b are alsopresented to other viewers without revealing the identity of the commentposter. For example, each comment posting may also include a genericavatar 706 associated with the comment posting. In some instances, aparticular user may view a comment posting (or in some cases, a messageposting) made by another user that the particular user does not follow.In some such instances, the particular user can elect to follow theother user even if the other user is not presented by system 112 as asuggested user to follow (e.g., in discover tab 602). In some cases, thesystem 112 may suggest to a particular user as a potential user tofollow (e.g., by presenting the user in the particular user's discovertab 602), a user that comments on message postings by users theparticular user does follow.

In some instances, if a comment poster posts multiple comment postingson the same message posting, the same generic avatar 706 will beassociated with each comment posting, such that viewers will know all ofthe content for a particular message posting that is provided by asingle user. However, in some cases, if that same user posts a commentposting on a different message posting, a different avatar may be used.Similarly, if the original message poster posts a comment posting onhis/her message, the same avatar 610 associated with the originalmessage posting may be associated with the comment posting. However, insome cases, if the original message poster posts a different messageposting, a different avatar may be used. In other cases, the same avatarmay be used for all message postings and/or comments posted by aparticular user.

Message postings 606 a, 606 b may also include an invite icon 620 which,when selected by a user, allows a user to invite another user (e.g., auser for which the message posting would not normally appear on his/herfeed tab 604) to comment on a particular message posting. In some cases,the invite icon 620 may be presented on a comment posting 702 a, 702 b.In some implementations, the system 122 may track each time a feedbackicon 614, repost icon 616, and/or comment icon 618 is selected for aparticular message posting. In some such implementations, the userinterface 600 may display such numbers on the message postings. Forexample, in FIG. 6, the feedback icon 614 has been selected 32 times,the comment icon 618 has been selected 120 times, and the repost iconhas been selected 0 times.

In various implementations, user interface 600 may also include ahistory tab 622. The history tab 622 may generally display content thatfor various reasons is no longer displayed in the feed tab 604. Ingeneral, content (e.g., message postings) may be relocated from the feedtab 604 to the history tab 622 whenever the content becomes lessrelevant, for example, if it has been posted for a particular amount oftime (e.g., 3 days), and/or if it has not received attention from users(e.g., feedback icon selection, comment postings. etc.) for a particularamount of time. In some instances, users can search content in thehistory tab 622 (e.g., via keyword). In some instances, e.g., if aparticular user discovers a posting in the history tab 622 for whichthere is interest in generating additional discussion/commentary, theparticular user can cause a posting in the history tab 622 to bepresented (or in some cases, re-presented) in the feed tab 604 of otherusers. This action may be performed by selecting the repost icon 616, oranother icon.

Various implementations of the system 112 may present content (e.g.,message postings) in various orders to content viewers. For example, insome instances, the order in which content is presented can be afunction of time (e.g., the newest posts appearing at the top of thefeed). In other instances, the order in which content is presented canbe based on the reputation of the poster. A poster's reputation can bebased on the feedback the poster has received on prior posts. Forexample, the reputation can be based on the number of “Thank you,” “Nothanks,” or other selections of the feedback icon 614. In some cases,there can be multiple levels of positive (or negative) feedbackindicating that a particular post was distinctive (e.g., candid,thoughtful, inspiring, etc.). In such cases, a reputation can beadditionally positively (or negatively) affected beyond the effect ofstandard feedback, based on receipt of such distinctive feedback. Inother cases, a poster's reputation can be based on the context in whichthe user received feedback. The context in which a user receivesfeedback can include the number of comments on a posting and/or thetotal amount of feedback received on a particular posting and itsassociated comments. For example, feedback received on a comment in alist of many (e.g., 100) comments, can have a greater effect on areputation than feedback received on a comment in a list of a few (e.g.,3) comments. As another example, feedback received on a comment in alist of many comments on which no (or little) other feedback isreceived, can have a greater effect on a reputation than feedbackreceived on a comment in a list of many comments on which large amountsof feedback is received.

In these instances, posts can be presented at a location on other users'feeds based on the poster's reputation (e.g., posts from posters withhigher reputations at higher locations, and posts from posters withlower reputations at lower locations). In some cases, the reputation ofa user can be categorized within a particular attribute (e.g., a jobtitle). For example, a particular user may have a high reputation for afounder, and the system 112 may favor presenting that user's posts tocertain users (e.g., other founders, or other users interested infounders, for example, as determined by their interactions withfounder's posts), but not favor presenting the user's posts to otherusers (e.g., designers, or other users not interested in founders).

In some cases, the reputation of a user can be categorized within aparticular topic. In order to do this, the posting user and/or anadministrator of the system 112 may assign a topic tag to at least someof the posts made using the system 112. By tracking the feedbackreceived on each post, as well as the topic tag assigned to each post, areputational score can be developed for a particular user in relation toa particular topic. For example, a particular user may receive a largeamount of positive feedback for his/her posts regarding fundraising, butless feedback (or less positive feedback) for his/her posts regardingrecruiting. As a result, the user may be assigned a high reputationalscore for fundraising and a low reputational score for recruiting. Suchtopic-based tagging of posts, and topic-based reputational scores, canbe used by the system 112 to determine how to present content to otherusers. For example, if a particular user interacts often withfundraising tagged content, the system 112 can present the particularuser with more content from other user's that have a high reputationalscore related to fundraising. In some cases, the content presented fromother user's with a high reputational score related to a topic aparticular user is interested in, need to not relate to the particulartopic. For example, if a particular user is interested in fundraising,the system 112 may present the user with the posts from another userthat has a very high reputational score related to fundraising topics,even if the particular post being presented from the other user relatesto another topic (e.g., recruiting).

Calculation of the reputation of a particular user can be based on theamount of feedback received by the user's posts, the topic tag assignedto the posts, as well as the attributes and/or reputation of the otheruser's providing the feedback. For example, if a user receives a largeamount of positive feedback on a post regarding fundraising, the user'sreputational score for fundraising may increase. But, for example, if afirst user and a second user receive the same amount of feedback for apost regarding fundraising, and the first user receives feedback fromprimarily user's that have a high fundraising reputational score, andthe second user receives feedback from primarily user's that do not havea high fundraising reputational score, then first user's fundraisingreputational score may increase more than the second user's fundraisingreputational score, based on the reputations of those users providingfeedback. A similar concept can be applied to attribute-based (e.g., jobtitle) reputation. For example, if a first user and a second userreceive the same amount of positive feedback on a particular post, butthe first user receives more positive feedback from founders, than thesecond user, then the first user's reputational score among founders mayincrease more than the second user's reputational score among founder.Similar concepts can be applied to other attribute-based and topic-basedreputational scores.

One example technique for calculating a reputational score of a user,applying some of the concepts described above is as follows. For aparticular topic, the system 112 may assign each user an initial scorebased on the number of other users that provided feedback (e.g.,“thanked”) the user regarding that topic. For example, for the topic offundraising, if User A was “thanked” by 50 other people and User B wasthanked by 10 other people, then User A can be assigned an initial scoreof 50, and User B can be assigned an initial score of 10. Once theinitial score is assigned, a particular user's score can be dispersed toother users that received feedback from the particular user regardingthe relevant topic, e.g., such that the other users' scores are affectedproportional to the reputational score of the particular user. Forexample, if User A thanked 10 people regarding fundraising, then eachperson User A thanked could have their reputational score increased by:

User A's initial score/the number of users User A provided feedback toApplying the above equation to this example would result in 50/10=5.Thus, if User A thanked User B regarding a fundraising post, User B'sreputational score for fundraising would be increased 5 points to 15.This process can then be repeated in iterations. For example, User B'sreputational score can then be dispersed to the other users that User Bprovided feedback to regarding fundraising. In some cases, the effect ofUser B's feedback can be decreased by a multiplier to reflect that it isbeing applied in a subsequent iteration. For instance, if User B thanked2 users—User C and User D—for posts regarding fundraising, then User Cand User D could have their reputational scores increased by:

(User B's initial score/the number of users User B provided feedbackto)×(a subsequent iteration multiplier)

Using an example subsequent iteration multiplier of 0.5, applying theabove equation to this example would result in (15/2)×0.5=3.75. Thus,User C and User D could have their reputational scores for fundraisingincreased by 3.75. A predetermined number of iterations (e.g., 4) canoccur, with the subsequent iteration multiplier being decreased for eachiteration. A similar example technique can be applied to determine anattribute-based reputational score (as opposed to a topic-based one). Inaddition to tracking a user's topic-based and/or attribute-basedreputational scores; in some implementations, the system 112 mayaggregate the reputational scores of a user across all topics (orattributes) to determine an aggregate reputational score for each user.

In other instances, content can be presented based on the reputation ofa particular post (as opposed to the reputation of the poster). Forexample, if a user indicates an interest in fundraising topics, theposts having a fundraising topic tag can be presented in an order basedon the feedback they have received (e.g., posts with the most positivefeedback first). The various techniques for presenting content (e.g.,time-based, poster-reputation-based, post-reputation-based, etc.) can beexecuted by the system 112 simultaneously, or as alternatives to oneanother. In instances in which the various techniques (or subsetsthereof) are executed simultaneously, a user can toggle betweendifferent feeds that present the content using the various techniques.For example, a first feed may present the newest content first, a secondfeed may present content based on the reputation of the posters for aparticular topic the user is interested in, and the third feed maypresent content based on the reputation of the posts for a particulartopic the user is interested in.

In various implementations, user interface 600 may include a home screen(e.g., presented upon election of home icon 624) that allows users totoggle between the discover tab 602, the feed tab 604, and the historytab 622. User interface 600 may also include a private messages screen(e.g., presented upon election of messages icon 626) that allows theuser to view and exchange private messages with other users. A privatemessage may be a message that cannot be commented on or interacted withby any users other than the users exchanging the private message. Userinterface 600 may also include a profile (“Me”) screen (e.g., presentedupon election of the “Me” icon 628) that allows a user to edit theinformation provided to the system 122 (e.g., job title, skills, and/orother attributes).

In various implementations, the social media platform established bysystem 622 can enable users to create content (e.g., messages) to beposted. In some instances, user interface 600 can present a compose icon630, upon selection of which a user is provided the ability to generatecontent to be posted. FIG. 8 illustrates an example user interface 800that enables a user to generate content. In some instances, the userinterface 800 may include a content field 802 (e.g., a text box) intowhich a user may insert a message (or in some cases in which a spokenmessage appears after being processed by voice recognition software). Inother instances, other content types (e.g., image, video, othermultimedia content, etc.) can be inserted. In some cases, the system 122places a limit on the size of a particular content post (e.g., acharacter limit for text message postings). In such cases a contentlimit icon 804 can display the available content remaining (e.g., numberof characters). In other cases, no limit is placed on the size of aparticular content post.

In certain implementations, a posting user can select other users ofsystem 122 that can view the content posting (e.g., which users willhave the content posting appear on their feed tab 604). In someinstances, user interface 800 may include a viewer identifier portion806 which a user can engage to perform such identifications. In general,a posting user can select any and all users of system 122, including anysubsets thereof, to view a particular message content posting. Whatfollows are descriptions of illustrative, but by no means exhaustive,examples of viewers that can be identified in various embodiments.

As shown in FIG. 8, in some instances, a posting user can select otherusers that follow the posting user (“followers”) as the viewers of aparticular content posting. In some cases, this means that the contentposting will appear on the feed tab 604 of any users that follow theposting user. In some cases, a posting user may further limit theviewers of a particular content by selecting only particular subsets ofcategories of users. An example of this concept is shown in FIG. 9; inaddition to limiting the viewers to followers, the posting user mayfurther limit the viewers to those followers that have particularattributes, for example, a particular job title (e.g., designers) orparticular skills (e.g., UI designers, artists, UX designers, etc.). Asshown, for example, in FIG. 9, a posting user may select categories (andsubcategories) of viewers by, for example, selecting icons identifyinguser subsets. In some cases, system 122 may determine certain categoriesand subcategories of viewers likely to be identified by the postinguser, and present such icons to the posting user in user interface 800.In some cases, if the user wishes to select user subsets not presentedvia an icon, he or she can indicate a desire to be given additionaloptions, e.g., by selecting a “+ more” icon 902. Upon selecting the “+more” icon 912, a user may be presented with more user subsets (e.g.,parents, immigrants, etc.), or in some cases may be given the option tosearch for other user subsets (e.g., a textual search by subset name).In certain implementations, each of the user subsets presented assubcategories under the follower category in FIG. 9, can be identifiedas categories as well. As one example, a posting user that is a designermay select all designers as viewers, regardless of whether they arefollowers.

In other instances, a posting user can select user subsets other thanfollowers as viewers. In order to do so, in one example, the user mayselect an “others” icon 1002 (FIG. 10) included in user interface 800.Once selected, the user can then select other user subsets (e.g., byselecting an icon 1004 identifying the other user subset) to view thecontent posting. Similar to the process outlined above, categories orsubcategories can be presented to the posting user, and/or the user mayperform searches for particular user subsets. FIG. 11 illustrates anexample user interface 1100 that a posting user can engage to search foruser subsets. In some cases, the system 122 can suggest additional usersubsets (e.g., job titles) that the posting user may be interested inselecting. In some situations, selecting viewers other than followerscan be useful for a posting user that desires the input of a subset ofusers that do not (or are unlikely to) follow the posting user. Forexample, consider the example of a posting user that is a designer andis followed by primarily other designers. Imagine the designer wants topost a question regarding the future of interface design, and isinterested in the input of founders because they may be more focused onthe future of technologies than other designers. In implementations ofthe present disclosure, the posting user can select founders as viewersof the question, even if the founders are not followers of the designer.User subsets other than followers can be identified as viewers inaddition to, or in some cases as an alternative to, followers.

As discussed above, in some implementations, selecting a user as aviewer results in the content posting appearing on the identified user'sfeed tab 604. In some instances, the identified users may include a verylarge number of users. For example, selecting all founders as viewersmay result in thousands or even millions of users being identified. Insuch instances, the system 122 may only post the content posting on aportion of the identified user's feed tabs. The portion may bedetermined randomly, or in some cases based on a degree of similarityand/or connection with the posting user (e.g., based on attributes,geographic location, etc.).

Referring again to FIG. 6, in implementations in which content appearingon a particular user's feed tab may include postings made by other usersthe particular user follows and other users the particular user does notfollow, user interface 600 can visually differentiate between thesedifferent types of posts. In general, the user interface 600 candifferentiate the posts in any way that enables the particular user toappreciate the difference in source. For example, posts from users notfollowed by the particular user may include an additional heading 632.As other examples, different shading, styles, color schemes, and/oravatar themes can be used to differentiate posts from different sources.

In still other instances, a posting user can select colleagues asviewers. As stated above, one item of information a user can providesystem 122 is their employer. In such instances, an identified categoryof viewers can be a posting user's colleagues, regardless of whether thecolleagues are followers of the posting user. FIG. 12 shows an exampleviewer identifier portion 806 upon selecting colleagues as viewers (inthis example, the employer is a company named “BetterCompany”). For aposting user with multiple employers, multiple identification optionsmay be provided. Of course, as described above, this category can befurther limited to subcategories as well (e.g., a user can select asviewers, other users that are colleagues, designers, and parents).Similar to visual differentiation between posts from a followed and anon-followed user described above, user interface 600 can employ similartechniques to differentiate posts from colleagues. The above describesonly a limited subset of example categories/subcategories of viewersthat can be identified. Many other examples are possible.

Operating Apparatus

FIG. 13 shows an example of a generic computing device 1350, which maybe used with some of the techniques described in this disclosure (e.g.,as client device 120 a, 120 b, 120 c). Computing device 1350 includes aprocessor 1352, memory 1364, an input/output device such as a display1354, a communication interface 1366, and a transceiver 1368, amongother components. The device 1350 may also be provided with a storagedevice, such as a microdrive or other device, to provide additionalstorage. Each of the components 1350, 1352, 1364, 1354, 1366, and 1368,are interconnected using various buses, and several of the componentsmay be mounted on a common motherboard or in other manners asappropriate.

The processor 1352 can execute instructions within the computing device1350, including instructions stored in the memory 1364. The processormay be implemented as a chipset of chips that include separate andmultiple analog and digital processors. The processor may provide, forexample, for coordination of the other components of the device 1350,such as control of user interfaces, applications run by device 1350, andwireless communication by device 1350.

Processor 1352 may communicate with a user through control interface1358 and display interface 1356 coupled to a display 1354. The display1354 may be, for example, a TFT LCD (Thin-Film-Transistor Liquid CrystalDisplay) or an OLED (Organic Light Emitting Diode) display, or otherappropriate display technology. The display interface 1356 may compriseappropriate circuitry for driving the display 1354 to present graphicaland other information to a user. The control interface 1358 may receivecommands from a user and convert them for submission to the processor1352. In addition, an external interface 1362 may be provided incommunication with processor 1352, so as to enable near areacommunication of device 1350 with other devices. External interface 1362may provide, for example, for wired communication in someimplementations, or for wireless communication in other implementations,and multiple interfaces may also be used.

The memory 1364 stores information within the computing device 1350. Thememory 1364 can be implemented as one or more of a computer-readablemedium or media, a volatile memory unit or units, or a non-volatilememory unit or units. Expansion memory 1374 may also be provided andconnected to device 1350 through expansion interface 1372, which mayinclude, for example, a SIMM (Single In Line Memory Module) cardinterface. Such expansion memory 1374 may provide extra storage spacefor device 1350, or may also store applications or other information fordevice 1350. Specifically, expansion memory 1374 may includeinstructions to carry out or supplement the processes described above,and may include secure information also. Thus, for example, expansionmemory 1374 may be provided as a security module for device 1350, andmay be programmed with instructions that permit secure use of device1350. In addition, secure applications may be provided via the SIMMcards, along with additional information, such as placing identifyinginformation on the SIMM card in a non-hackable manner.

The memory may include, for example, flash memory and/or NVRAM memory,as discussed below. In one implementation, a computer program product istangibly embodied in an information carrier. The computer programproduct contains instructions that, when executed, perform one or moremethods, such as those described above. The information carrier is acomputer- or machine-readable medium, such as the memory 1364, expansionmemory 1374, memory on processor 1352, or a propagated signal that maybe received, for example, over transceiver 1368 or external interface1362.

Device 1350 may communicate wirelessly through communication interface1366, which may include digital signal processing circuitry wherenecessary. Communication interface 1366 may in some cases be a cellularmodem. Communication interface 1366 may provide for communications undervarious modes or protocols, such as GSM voice calls, SMS, EMS, or MMSmessaging, CDMA, TDMA, PDC, WCDMA, CDMA2000, or GPRS, among others. Suchcommunication may occur, for example, through radio-frequencytransceiver 1368. In addition, short-range communication may occur, suchas using a Bluetooth, WiFi, or other such transceiver (not shown). Inaddition, GPS (Global Positioning System) receiver module 1370 mayprovide additional navigation- and location-related wireless data todevice 1350, which may be used as appropriate by applications running ondevice 1350.

Device 1350 may also communicate audibly using audio codec 1360, whichmay receive spoken information from a user and convert it to usabledigital information. Audio codec 1360 may likewise generate audiblesound for a user, such as through a speaker, e.g., in a handset ofdevice 1350. Such sound may include sound from voice telephone calls,may include recorded sound (e.g., voice messages, music files, etc.) andmay also include sound generated by applications operating on device1350.

The computing device 1350 may be implemented in a number of differentforms, as shown in FIG. 13. For example, it may be implemented as acellular telephone 1380. It may also be implemented as part of asmartphone 1382, smart watch, personal digital assistant, or othersimilar mobile device.

Operating Environment

Some implementations of the subject matter and the operations describedin this specification can be implemented in digital electroniccircuitry, or in computer software, firmware, or hardware, including thestructures disclosed in this specification and their structuralequivalents, or in combinations of one or more of them. Implementationsof the subject matter described in this specification can be implementedas one or more computer programs, i.e., one or more modules of computerprogram instructions, encoded on computer storage medium for executionby, or to control the operation of, data processing apparatus.Alternatively or in addition, the program instructions can be encoded onan artificially-generated propagated signal, e.g., a machine-generatedelectrical, optical, or electromagnetic signal, that is generated toencode information for transmission to suitable receiver apparatus forexecution by a data processing apparatus. A computer storage medium canbe, or be included in, a computer-readable storage device, acomputer-readable storage substrate, a random or serial access memoryarray or device, or a combination of one or more of them. Moreover,while a computer storage medium is not a propagated signal, a computerstorage medium can be a source or destination of computer programinstructions encoded in an artificially-generated propagated signal. Thecomputer storage medium can also be, or be included in, one or moreseparate physical components or media (e.g., multiple CDs, disks, orother storage devices).

The operations described in this specification can be implemented asoperations performed by a data processing apparatus on data stored onone or more computer-readable storage devices or received from othersources.

The term “data processing apparatus” encompasses all kinds of apparatus,devices, and machines for processing data, including by way of example aprogrammable processor, a computer, a system on a chip, or multipleones, or combinations, of the foregoing. The apparatus can includespecial purpose logic circuitry, e.g., an FPGA (field programmable gatearray) or an ASIC (application-specific integrated circuit). Theapparatus can also include, in addition to hardware, code that createsan execution environment for the computer program in question, e.g.,code that constitutes processor firmware, a protocol stack, a databasemanagement system, an operating system, a cross-platform runtimeenvironment, a virtual machine, or a combination of one or more of them.The apparatus and execution environment can realize various differentcomputing model infrastructures, such as web services, distributedcomputing and grid computing infrastructures.

A computer program (also known as a program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, declarative orprocedural languages, and it can be deployed in any form, including as astand-alone program or as a module, component, subroutine, object, orother unit suitable for use in a computing environment. A computerprogram may, but need not, correspond to a file in a file system. Aprogram can be stored in a portion of a file that holds other programsor data (e.g., one or more scripts stored in a markup languageresource), in a single file dedicated to the program in question, or inmultiple coordinated files (e.g., files that store one or more modules,sub-programs, or portions of code). A computer program can be deployedto be executed on one computer or on multiple computers that are locatedat one site or distributed across multiple sites and interconnected by acommunication network.

The processes and logic flows described in this specification can beperformed by one or more programmable processors executing one or morecomputer programs to perform actions by operating on input data andgenerating output. The processes and logic flows can also be performedby, and apparatus can also be implemented as, special purpose logiccircuitry, e.g., an FPGA (field programmable gate array) or an ASIC(application-specific integrated circuit).

Processors suitable for the execution of a computer program include, byway of example, both general and special purpose microprocessors, andany one or more processors of any kind of digital computer. Generally, aprocessor will receive instructions and data from a read-only memory ora random access memory or both. The essential elements of a computer area processor for performing actions in accordance with instructions andone or more memory devices for storing instructions and data. Generally,a computer will also include, or be operatively coupled to receive datafrom or transfer data to, or both, one or more mass storage devices forstoring data, e.g., magnetic, magneto-optical disks, or optical disks.However, a computer need not have such devices. Moreover, a computer canbe embedded in another device, e.g., a mobile telephone, a personaldigital assistant (PDA), a mobile audio or video player, a game console,a Global Positioning System (GPS) receiver, or a portable storage device(e.g., a universal serial bus (USB) flash drive), to name just a few.Devices suitable for storing computer program instructions and datainclude all forms of non-volatile memory, media and memory devices,including by way of example semiconductor memory devices, e.g., EPROM,EEPROM, and flash memory devices; magnetic disks, e.g., internal harddisks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROMdisks. The processor and the memory can be supplemented by, orincorporated in, special purpose logic circuitry.

To provide for interaction with a user, implementations of the subjectmatter described in this specification can be implemented on a computerhaving a display device, e.g., a CRT (cathode ray tube) or LCD (liquidcrystal display) monitor, for displaying information to the user and akeyboard and a pointing device, e.g., a mouse or a trackball, by whichthe user can provide input to the computer. Other kinds of devices canbe used to provide for interaction with a user as well; for example,feedback provided to the user can be any form of sensory feedback, e.g.,visual feedback, auditory feedback, or tactile feedback; and input fromthe user can be received in any form, including acoustic, speech, ortactile input. In addition, a computer can interact with a user bysending resources to and receiving resources from a device that is usedby the user; for example, by sending web pages to a web browser on auser's client device in response to requests received from the webbrowser.

Implementations of the subject matter described in this specificationcan be implemented in a computing system that includes a back-endcomponent, e.g., as a data server, or that includes a middlewarecomponent, e.g., an application server, or that includes a front-endcomponent, e.g., a client computer having a graphical user interface ora Web browser through which a user can interact with an implementationof the subject matter described in this specification, or anycombination of one or more such back-end, middleware, or front-endcomponents. The components of the system can be interconnected by anyform or medium of digital data communication, e.g., a communicationnetwork. Examples of communication networks include a local area network(“LAN”) and a wide area network (“WAN”), an inter-network (e.g., theInternet), and peer-to-peer networks (e.g., ad hoc peer-to-peernetworks).

The computing system can include clients and servers. A client andserver are generally remote from each other and typically interactthrough a communication network. The relationship of client and serverarises by virtue of computer programs running on the respectivecomputers and having a client-server relationship to each other. In someimplementations, a server transmits data (e.g., an HTML page) to aclient device (e.g., for purposes of displaying data to and receivinguser input from a user interacting with the client device). Datagenerated at the client device (e.g., a result of the user interaction)can be received from the client device at the server.

A system of one or more computers can be configured to performparticular operations or actions by virtue of having software, firmware,hardware, or a combination of them installed on the system that inoperation causes or cause the system to perform the actions. One or morecomputer programs can be configured to perform particular operations oractions by virtue of including instructions that, when executed by dataprocessing apparatus, cause the apparatus to perform the actions.

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of anyinventions or of what may be claimed, but rather as descriptions offeatures specific to particular implementations of particularinventions. Certain features that are described in this specification inthe context of separate implementations can also be implemented incombination in a single implementation. Conversely, various featuresthat are described in the context of a single implementation can also beimplemented in multiple implementations separately or in any suitablesubcombination. Moreover, although features may be described above asacting in certain combinations and even initially claimed as such, oneor more features from a claimed combination can in some cases be excisedfrom the combination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. In certain circumstances, multitasking and parallel processingmay be advantageous. Moreover, the separation of various systemcomponents in the implementations described above should not beunderstood as requiring such separation in all implementations, and itshould be understood that the described program components and systemscan generally be integrated together in a single software product orpackaged into multiple software products.

Thus, particular implementations of the subject matter have beendescribed. Other implementations are within the scope of the followingclaims. In some cases, the actions recited in the claims can beperformed in a different order and still achieve desirable results. Inaddition, the processes depicted in the accompanying figures do notnecessarily require the particular order shown, or sequential order, toachieve desirable results. In certain implementations, multitasking andparallel processing may be advantageous.

What is claimed is:
 1. A method comprising: performing by one or morecomputers: identifying a first group of users of a plurality of userswherein each of the users in the first group has a respective likenessscore in relation to a first user that satisfies a threshold, andwherein each user of the first group is permitted to send anonymousmessages through a respective account to the first user; identifying aplurality of first anonymous messages received in an account of thefirst user, each first message having been authored by a respective userof the first group; and obtaining user input of the first usercomprising selection of an icon indicating a negative response to aparticular first message and, based thereon, removing an author of theparticular first message from the first group such that the author is nolonger permitted to send messages to the first user through the accountof the author.
 2. The method of claim 1, further comprising: afterremoval of the author from the first group, determining respectivelikeness scores of one or more particular users in relation to the firstuser and, based thereon, adding the particular users to the first groupor removing the particular users from the first group.
 3. The method ofclaim 2, wherein removing the particular users from the first groupfurther comprises: determining that respective likeness scores of theparticular users no longer satisfy the threshold and, based thereon,removing the particular users from the first group such that the removedparticular users are no longer permitted to send messages to the firstuser through their respective accounts.
 4. The method of claim 2,wherein adding the particular users to the first group furthercomprises: determining that a second group of one or more of theplurality of users have respective likeness scores that satisfy thethreshold after removal of the author from the first group; and addingthe second group of users to the first group of users such that eachuser of the second group is permitted to send anonymous messages througha respective account to the first user.
 5. The method of claim 2,wherein determining the respective likeness scores of the particularusers in relation to the first user, comprises: identifying one or morediscriminating attributes; obtaining a weighted vector of attributes forthe first user and for each of the particular users; adjusting arespective weight of the discriminating attributes in each of thevectors; and calculating the respective likeness score of each of theparticular users as a difference between the weighted vector ofattributes of the particular user and the weighted vector of attributesof the first user.
 6. The method of claim 5, wherein identifying one ormore discriminating attributes comprises identifying one or morediscriminating attributes of the author.
 7. The method of claim 5,wherein identifying the discriminating attribute comprises clusteringthe plurality of users based on respective attributes of the users toidentify the discriminating attributes that influence clustermembership.
 8. The method of claim 7, wherein clustering comprises: fordifferent pairs of users of the plurality of users, calculating arespective distance between the users of the pair based on therespective attributes of the users in the pair; and clustering usersbased on the distances.
 9. The method of claim 5, wherein a particularattribute comprises one or more respective anonymous answers, submittedthrough respective accounts of the particular users to one or morequestions submitted through the account of the first user.
 10. Themethod of claim 5, wherein a particular attribute comprises aprofession, a company, time of employment, location of employment, or anattribute that is unrelated to employment.
 11. The method of claim 5,wherein a particular attribute comprises a respective positive responseto an anonymous message through an account of a user.
 12. A systemcomprising: one or more computers programmed to perform operationscomprising: identifying a first group of users of a plurality of userswherein each of the users in the first group has a respective likenessscore in relation to a first user that satisfies a threshold, andwherein each user of the first group is permitted to send anonymousmessages through a respective account to the first user; identifying aplurality of first anonymous messages received in an account of thefirst user, each first message having been authored by a respective userof the first group; and obtaining user input of the first usercomprising selection of an icon indicating a negative response to aparticular first message and, based thereon, removing an author of theparticular first message from the first group such that the author is nolonger permitted to send messages to the first user through the accountof the author.
 13. The system of claim 12, wherein the operationsfurther comprises: after removal of the author from the first group,determining respective likeness scores of one or more particular usersin relation to the first user and, based thereon, adding the particularusers to the first group or removing the particular users from the firstgroup.
 14. The system of claim 13, wherein removing the particular usersfrom the first group further comprises: determining that respectivelikeness scores of the particular users no longer satisfy the thresholdand, based thereon, removing the particular users from the first groupsuch that the removed particular users are no longer permitted to sendmessages to the first user through their respective accounts.
 15. Thesystem of claim 13, wherein adding the particular users to the firstgroup further comprises: determining that a second group of one or moreof the plurality of users have respective likeness scores that satisfythe threshold after removal of the author from the first group; andadding the second group of users to the first group of users such thateach user of the second group is permitted to send anonymous messagesthrough a respective account to the first user.
 16. The system of claim13, wherein determining the respective likeness scores of the particularusers in relation to the first user, comprises: identifying one or morediscriminating attributes; obtaining a weighted vector of attributes forthe first user and for each of the particular users; adjusting arespective weight of the discriminating attributes in each of thevectors; and calculating the respective likeness score of each of theparticular users as a difference between the weighted vector ofattributes of the particular user and the weighted vector of attributesof the first user.
 17. The system of claim 16, wherein identifying oneor more discriminating attributes comprises identifying one or morediscriminating attributes of the author.
 18. The system of claim 16,wherein identifying the discriminating attribute comprises clusteringthe plurality of users based on respective attributes of the users toidentify the discriminating attributes that influence clustermembership.
 19. The system of claim 18, wherein clustering comprises:for different pairs of users of the plurality of users, calculating arespective distance between the users of the pair based on therespective attributes of the users in the pair; and clustering usersbased on the distances.
 20. The system of claim 16, wherein a particularattribute comprises one or more respective anonymous answers, submittedthrough respective accounts of the particular users to one or morequestions submitted through the account the first user.
 21. The systemof claim 16, wherein a particular attribute comprises a profession, acompany, time of employment, location of employment, or an attributethat is unrelated to employment.
 22. The system of claim 16, wherein aparticular attribute comprises respective positive response to ananonymous message through an account of a user.